What is the criteria to label anembryonic gestation?
More than or equal to 25 mm mean sac diameter, with absence of fetal pole, is considered anembryonic gestation
No fetal pole is present within this 25 mm intrauterine gestational sac. This is in keeping with an anembryonic pregnancy (older term - "blighted ovum"). The irregular shape of the gestational sac is also regarded as a poor prognostic factor.